Auto-Gen Cruising Generator

New purchase of a Grand Banks 42' Classic and getting to know her. We had to
put in a new transfer switch to distribute the electric power sources. The boat has an Auto-Gen shaft generator, and we don't know how it should be wired or how to use it. Of course, some really BAD things can/will happen when electricity gets messed up, so we're trying to find out about this crusing generator.
We do have a 8KW Onan and it feeds into a voltage regulator (also Auto-Gen) along with the Crusing Generator. From there I think it should go to the "generator" post on the transfer switch. 'Just trying to work this through my head and appreciate others that know this system.

Thanks

Welcome aboard and congrats on your new boat. Now the fun part of figuring it all out.

Galey said:

New purchase of a Grand Banks 42' Classic and getting to know her. We had to
put in a new transfer switch to distribute the electric power sources. The boat has an Auto-Gen shaft generator, and we don't know how it should be wired or how to use it. Of course, some really BAD things can/will happen when electricity gets messed up, so we're trying to find out about this crusing generator.
We do have a 8KW Onan and it feeds into a voltage regulator (also Auto-Gen) along with the Crusing Generator. From there I think it should go to the "generator" post on the transfer switch. 'Just trying to work this through my head and appreciate others that know this system.

Thanks

Click to expand...

I'll need some help here. What's and "Auto-gen shaft generator"? And what is the "auto-gen regulator that the 8kw Onan feeds into? Sounds like a very unique system.

Auto-gen

Auto-gen is the company/brand. I also have a 8 KW onan; they both hook up through an Auto-Gen regulator, and I’m trying to learn how all that works. That regulator then goes to the transfer switch, and when “gen” is selected, one or the other feeds the electric panel box. That’s the best understanding I have at this time. The Auto-Gen is a “cruising” generator 3.5 KW running off a main engine.

Galey said:

Auto-gen is the company/brand. I also have a 8 KW onan; they both hook up through an Auto-Gen regulator, and I’m trying to learn how all that works. That regulator then goes to the transfer switch, and when “gen” is selected, one or the other feeds the electric panel box. That’s the best understanding I have at this time. The Auto-Gen is a “cruising” generator 3.5 KW running off a main engine.

Click to expand...

Thanks. Any chance of some pictures?

Does this "Auto Gen" produce DC or AC? If AC it would have to be built with inverter technology like the Honda EU 2000i due to the variable speed of the prop shaft. I googled "Auto Gen Cruising Generator" and couldn't find anything.

David

This is the page from the Ford Lehman catalog.

https://www.trawlerforum.com/forums/attachment.php?attachmentid=131506&stc=1&d=1661425793

I don't really know the answer to the ac/dc question, but think it's ac. Hoping for good information on it. Maybe the best way to go is with lithium batteries and
a 3000 watt inverter. Still looking for answers.

Thanks

I remember these devices. They predated inverters for 120vac power and were often mounted on work truck engines (belt drive). I would treat it as an alternative AC source, same as if you had an inverter, though it's possible (probable?) The Auto-Gen transfer switch has some sort of relay to engage the magnetic clutch on the Auto-Gen generator. I am now beyond my technical leash, so speculation at best.

Question really comes down to how the transfer switch operates and number of inputs it will accept. Sounds like you have 3 existing inputs - shore power, generator, and the Auto-Gen. Attached pic of a common marine manual transfer switch (Newmar).

My guess is these have long been replaced by inverters and hi-output alternators.

Good luck and congrats on your new GB42. Timeless classic!

Peter
View attachment 131507

That's a very clever, if not dated system. It uses a variable ratio belt drive (like those used in ATVs) to drive the generator at a constant speed to produce 60hz AC power off the main engine regardless of main engine RPM.


If it were me, I'd remove all of it except the Onan generator, put a high-output alternator on the main engine in placed of the Autogen device, and install a 3-5kw inverter. You are going to have to do it anyway the first time the auto gen breaks, if it even still works.


Then I'd try to find a marine equipment museum to take the Auto Gen. It's too unique to not preserve it.

Good advice! ‘Sounds like a plan for us. Our focus has been on other projects, but the conversion to lithium/inverter is ‘on the list’.

Thanks for your reply…..

twistedtree said:

That's a very clever, if not dated system. It uses a variable ratio belt drive (like those used in ATVs) to drive the generator at a constant speed to produce 60hz AC power off the main engine regardless of main engine RPM.


If it were me, I'd remove all of it except the Onan generator, put a high-output alternator on the main engine in placed of the Autogen device, and install a 3-5kw inverter. You are going to have to do it anyway the first time the auto gen breaks, if it even still works.


Then I'd try to find a marine equipment museum to take the Auto Gen. It's too unique to not preserve it.

Click to expand...

I was going to say the same thing. That Auto-Gen device is definitely 110 V AC but based on ancient mechanical drive frequency regulation. Like noted above, it may not even work today.

A large battery bank, a high output DC alternator and a large inverter with an internal transfer switch will be your best bet to supply AC while cruising. Connect the inverter's output to your main AC system by "splitting the bus" as described here- https://www.trawlerforum.com/forums/downloads.php?do=file&id=118. Then if not already configured this way, wire your shore power and Onan generator output to a transfer switch.

David

We had one of those on our 1st boat-a 1972 GB42 w/Lehmans. Primarily used it to power 120ac Plath windlass motor. If I remember correctly, it had a gauge that would show when you were at the correct rpms to provide 120volts and then you would engage the clutch.

Tator

Hi,
My advice is that AC is not to be messed with without competent professional advice. I did a quick search and found that AutoGen is still in business and still selling generators and other gear. Have you tried calling them and asking for tech support? I solved a number of problems with our complicated AC systems by calling the Outback team since I had their inverter/chargers. They helped with the entire system integration. Good luck,
Ric

AutoGen

Would you share their contact info? I could not find them. Much appreciated

Ric said:

https://www.autogen.tech/products/power-station-pps-01

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Wrong Auto-Gen, their telephone number come back to Hongkong Santex Co, Ltd.

Sorry. I just enlarged the manual page above and saw it was made by Lehman Power. From a page on Lehman Power, I found "Fortunately, several aftermarket sources continue to provide replacement components including Bob Smith’s American Diesel, Bomac Marine Power, Bowman Ltd., Lancing Marine and Mermaid Marine Engines Ltd."
Perhaps an email query to one/all of those would get you somewhere.
Apologies for not digging deeper,
Ric